The Pats do what all coaching staffs are theoretically supposed to do - adjust their gameplan to match their opponent. Michel has a role as the bruiser back when they want to load up and go run heavy. Chargers putting 3 safeties on the field? Bludgeon those guys with 30 carries. The week after that, they'll go shotgun 4 wide and throw it all over the yard. The only constant with Belichick is that he's going to do what you don't want him to do.
Michel's not really a feature back in the chameleon-esque Patriots offense, but he's looking like a really nice piece who can strap up for 25 carries and turn it into 100 yards when the Hoodie deems it necessary.
I just looked it up, and out of the top 10 leading rushers this year, 5 of them were top 10 picks. 8 of them went in the first two rounds.
So if you want an elite rusher, a primo pick is the best way to get him.